The present disclosure generally relates to vehicle piloting. More particularly, the disclosure relates to using known automated lane keeping systems to adjust the position of a vehicle within the vehicle's currently occupied lane in response to a vehicle or obstacle detected in an adjacent lane.
Currently, there are known automated systems which help to ensure that a vehicle remains in an intended driving lane. Normally the lane keeping support function (also referred to herein as a “lane keeping system” causes the vehicle to assume a center position within the driving lane as an optimal driving position. An example of such a system is described in U.S. Pat. No. 5,913,375 which issued to Masao Nishikawa on Jun. 22, 1999 (hereinafter referred to as “the '375 patent” and fully incorporated in this disclosure by reference). FIG. 1 illustrates the components of the exemplary lane keeping system described in the '375 patent. Because the '375 patent is fully incorporated herein, a detailed description of the function of each component in FIG. 1 will not be repeated. In pertinent part, FIG. 1 shows the following components: a charge-coupled device (CCD) TV camera 10 mounted in the vehicle for capturing a view of the road ahead of the vehicle-including lines which function to mark the boundaries of driving lanes; front and side/back radars 12a and 12b, respectively (back radars not shown in FIG. 1), mounted in the vehicle to detect the presence of obstacles such as other vehicles in adjacent lanes; and a control unit 60 which processes the data obtained by the previously mentioned components and provides an output signal which is used to steer the vehicle and keep the vehicle centered within a particular driving lane—without driver intervention.
FIGS. 2a and 2b illustrate a more detailed exemplary schematic of the control unit of FIG. 1, as described in the '375 patent. The schematic of FIGS. 2a and 2b shows that control unit 60 includes a central microprocessor CPU1 which processes the data obtained by the camera 10. (This data may be referred to herein collectively as an example of “occupied lane boundary information” because it essentially represents the location of the outside lane lines of the driving lane currently occupied by the vehicle). A CPU2 processes the data obtained by side radars 12b in combination with the output of CPU1 and generates the output signal used to steer the vehicle (as mentioned above) via motor amplifier 62 and bias motor 34.
FIG. 3 illustrates an example of the driving lane boundary parameters analyzed by the control unit of FIG. 1, as described in the '375 patent. In FIG. 3, “N” represents the outside lane lines of the current driving lane, “M” represents the desired center driving line within the lane, “L” represents the distance between the outside lane line and the desired center driving line, and “δL” and “θV” enable the lane keeping system to keep track of how the vehicle is oriented with respect to the desired driving line. In summary, the '375 patent lane keeping system uses the parameters illustrated in FIG. 3 to keep the vehicle along desired driving line “M”.
The present disclosure appreciates the fact that, systems such as the example described in the '375 patent do not account for vehicles or other objects in lanes adjacent to the lane currently occupied by the vehicle. If a vehicle is present in the adjacent lane, and especially if the lanes are narrow and the lateral distance between the vehicles is small, a lateral displacement of the system-carrying vehicle in its own (“occupied”) lane is desirable to increase the lateral distance away from the adjacent vehicle. In addition, typical stand-alone lane keeping functions (“lane keeping systems”) disengage when the turn signal indicator is actuated signifying that the driver desires to change lanes. Thus, known systems provide no warning to a driver changing lanes of possible obstacles in the new driving position, such as another vehicle.
Thus, what is needed is a method and apparatus which overcomes the above mentioned shortcomings in the prior art.
In accordance with an embodiment of the present invention, a vehicle is piloted by first using a lane keeping system to detect objects in lanes adjacent to a lane occupied by the vehicle and then adjusting the position of the vehicle within the occupied lane, relative to at least one detected object.